The invention relates to an over-center, self-closing hinge for cabinet doors, having two hinge links pivoting in the manner of a four-joint hinge on a door-related hinge part at one end and on a jamb-related hinge part in the form of an elongated supporting arm at the other, and having a biased spring one end of which thrusts against the jamb-related pivot of the outer hinge link, i.e., the link more remote from the jamb, and whose other end thrusts against the inner hinge link, i.e., the link nearer the jamb, at a point at a distance froom its jamb-end pivot, so as to produce a hinge closing torque when the hinge is close to its closed position.
An over-center, self-closing hinge of this kind is known from U.S. Pat. No. 4,065,829, in which the spring under bias is an arcuately curved spring whose one end thrusts against the pivot of the outer hinge link while its other end engages a pin disposed transversely between two side plates formed on the inner hinge link. As a result of the distance between the transverse pin and the pin mounting the inner hinge link, the bias of the spring engages the inner hinge link with mechanical advantage, such that, as the hinge nears the closed position, a torque acting in the closing direction is produced by the bias, and, as it nears the open position, a torque acting in the opening direction is produced. The known hinge thus has an over-center characteristic which forces the hinge to one of its end positions depending on the angle of the hinge. For certain uses, however, over-center hinges are needed which produce a closing torque only in the vicinity of the closed position, while otherwise the hinge, along with the door mounted on it, can be moved to and fro without force or torque being applied by the spring.
It is therefore the object of the invention to create an over-center, self-closing hinge of this kind, namely one in which a closing torque acts only in the vicinity of the closed position, and to make the over-center mechanism producing this torque so compact that it can be disposed out of sight in the interior of the supporting arm.